Disclaimer Time
First things first: You NEED to play this game solo at least once all the way through. This game's unique take on horror and atmosphere should be first experienced ALONE. Knowing you have someone to back you up removes all feeling of terror and suspence. You have been warned.

If you decide on using it or if the non-Hamachi method doesn't work for you, the software used (Hamachi) in the following guide WILL ALLOW ANYONE ON YOUR VPN TO DIRECTLY ACCESS YOUR COMPUTER. Make sure you shut down Hamachi after you are done playing. I take ZERO responsibility for anything that may happen as a result of you or your friends not following those instructions.

This guide is long, you may need an afternoon to get through it and even then, it may not work at all. Whilst I have done my best to layout and explain how to get this working, there is no 100% guarantee this will work for you. I also can not help you with your own Network configurations or Firewalls. You are on your own.

This guide will assume that you have bought System Shock 2 from GOG.com or have Purchased it from Steam.

If you own the CD version of System Shock 2, you will need to patch it up to version 2.3 and apply the NewDark patch. You can do so by downloading and running SS2Tool in your System Shock 2 installation directory.

What you need to know about hosting a game
Here are some things you should know about Saving and Loading in Multiplayer: When a game is saved in Multiplayer Mode, it will be stored in a folder in your System Shock 2 Directory and can only be loaded in Multiplayer Mode from a unique save selection screen. Multiplayer saves will not be seen in Single Player mode and vice versa.

When either the host or a client pauses the game, it affects everyone in that current game until that player unpauses the game. You can still type messages to each other when the game is paused by pressing whichever key is assigned as the 'Chat' key in your key configuration.

If you're going to load a save, make sure you choose the right 'name' from your saved games. If you saved a session as 'OurPlaythrough' but don't choose that name for your saves at the multi-user access window then they will NOT appear when trying to load a previous session.

When a client disconnects from the game session, they will disappear and a box will be left behind in their place. This box contains all the items they picked up during their adventure. People CANNOT join a game in progress.

If you, the host, disconnect from the game then the game will still carry on. A box will not be dropped containing your items and it is best for everyone if everyone quits to the main menu and waits for you to set up another session.

What you need to know about hosting a game
Here are some things you should know about Saving and Loading in Multiplayer: When a game is saved in Multiplayer Mode, it will be stored in a folder in your System Shock 2 Directory and can only be loaded in Multiplayer Mode from a unique save selection screen. Multiplayer saves will not be seen in Single Player mode and vice versa.

When either the host or a client pauses the game, it affects everyone in that current game until that player unpauses the game. You can still type messages to each other when the game is paused by pressing whichever key is assigned as the 'Chat' key in your key configuration.

When you or another client, except the host, disconnects from the game session, they will disappear and a box will be left behind in their place. This box contains all the items they picked up during your/their adventure.

If the host disconnects from the game then the game will still carry on. A box will not be dropped containing their items and it is best for everyone if everyone quits to the main menu and waits for the host to set up another session.

How to connect without using Hamachi
It's possible to connect to each other without the need for Hamachi. The host will have to forward (open) a set of ports on their connection however.

Opening ports will vary from router to router so I can't help you with the specifics. You can find out more about Port Forwarding here.

If you are using a custom firewall such as Comodo, you may have to disable your Firewall Driver in your Local Area Network's Properties in the Network and Sharing Centre. Remember to re-enable it when you are done playing.

As long as any custom firewall driver is disabled, connecting to each other should work flawlessly. You may not even need to have the ports open at all to connect.

The Hamachi Method
If the method above hasn't worked for you, there is another way to try connecting. You will need to install some software on your computer called Hamachi. Hamachi, a VPN (Virtual Private Network) client, will help up to five computers to directly connect to each other. This will be perfect as the game can support up to four players.

In order to download the latest version of Hamachi and use the many functions it provides, you can either download Hamachi from FileHippo
OR
You can sign up for a free account at https://secure.logmein.com to download the software. After logging in, go to 'My Networks' in the Networks Tab on the left side of the page. Click 'Add Client', make sure that 'Install LogMeIn Hamachi on this computer' is checked and click Continue. Click Download Now to download the latest verion of Hamachi.

Everyone who will be playing Shock 2 will need to install the software and make a profile but but only ONE person will need to make a Hamachi Network and invite thier friends to join them on it. Decide who is doing what before you proceed with this guide.

Start Hamachi and click the 'Power On' button. If it asks you to give yourself a name then do so now. If it doesn't or you don't like the name you gave yourself, you can go to System > Preferences and Add/Change it.

Only one person needs to create a Hamachi Network and the other people join it.

To create a new network, click Network > Create New Network.

In the Network ID box, give your network a Unique Network ID and password. The ID can be words or numbers and is Caps sensitive. Now Click Create and you've created your own network.

Give the Unique ID to your friends. They should click on Network > Join an existing network and enter the information there to connect.

Skip down to the Getting ready to play section of this guide to proceed once all your friends have connected.

Creating a Hamachi Network (through the Hamachi Website)This is the section for you if you want to have maximum control over your Hamachi network. If you just want to create a quick network then I recommend you read the "Creating and Joining a Hamachi Network through the Hamachi client" section above.

Click the blue 'Add Network' button on the 'My Networks' page. Give the Network a Name and make sure 'Mesh' is selected from the 3 options provided and click continue.

Step 2 is really down to you and what you want from this network. For the sake of this guide, we will leave the Join Request option 'Accept Automatically' selected. Give the Network a password. This password you will need to give to your friends so that they can login to the network.

Free subscription will be selected by Default but if you want a subscription then go ahead and buy one.

Click Continue and finish on Step 3 to create your network. Your network will be given a Unique ID number consisting of nine numbered digits split into three groups of three (XXX-XXX-XXX). Your friends will need this Unique ID in order to connect to your network.

Connecting to the Hamachi Network
This is for everyone including the person making the network. Start Hamachi and click the 'power on' button. If it asks you to give yourself a name then do so now. If it doesn't or you don't like the name you gave yourself, you can go to System > Preferences and Add/Change it.

Click Network and select 'Join an Existing Network'. Enter in that nine digit Unique ID number of the network and the password to connect.

If you've done it all right, you'll see the name of the network appear light blue box and it should say 1/5 on the right. You've successfully made your own Hamachi Network for you and all your friends to join!

Getting Ready to Play
OK So we've gotten this far. Now all that's left is to start up the game and get connected.

Whoever is going to be hosting the game is going to give out either their Real IP address or their Hamachi IP address.The Hamachi IP address is one Hamachi gives you when you install the software. Your Hamachi IP will be displayed on the Hamachi client near the blue 'power on' button.

Let's say, for example, that you are going to host the game. If you are using Hamachi, your Hamachi IP is 12.345.67.890. Give your IP to your friends, start System Shock 2 and follow the relevant section below.

Choose a name for your saves if you want but remember that if you want to have multiple playthroughs with different people at the same time, you will need to change this name to something different and remember it. Enter your name for your character you'll be playing and click next.

Depending on which method you have used, you will need to either give out your real IP address or your Hamachi IP address to your fellow players.

You will then get to a window that will list all players in the current session on screen. Think of this as a 'Lobby' like Left 4 Dead. You will need to tell people that you are waiting for them to connect as this is the time to do it.

When all people have connected to your Lobby, Press Next.

You can either Start a New Game or Load a previously saved game. Make your choice and away you go.

When you start a New Game and don't see your friends next to you on the train, don't panic! You will not meet up with your friends until you get onto the Von Braun. You are free to explore the town on street level, find any hidden secrets, do the tutorials and do your Yearly Postings in which ever career you choose.

After your 3rd year of training, the game will attempt to 'synchronize' with your friends. If your friends are not up to their 3rd year of training by this point, you will be stuck on a temporary 'Synchronizing...' screen until they are all ready.

When everyone has completed their training. You'll all see the starting cutscene and then awaken upon the Von Braun.

Enter in the IP address the host has given you in here. If they haven't given you their IP, request it from them now. Give your character that you'll be playing a name.

The game will now try to connect to the IP you entered. If successful, you will see the host and yourself in a list. Think of this as a 'Lobby' like Left 4 Dead. You could start a new game if you want to but if the host has other plans then all you need to do is simply wait on this screen and everything will happen automatically as the host either starts a new game or loads a previous multiplayer save.

When you start a New Game and don't see your friends next to you on the train, don't panic! You will not meet up with your friends until you get onto the Von Braun. You are free to explore the town on street level, find any hidden secrets, do the tutorials and do your Yearly Postings in which ever career you choose.

After your 3rd year of training, the game will attempt to 'synchronize' with your friends. If your friends are not up to their 3rd year of training by this point, you will be stuck on a temporary 'Synchronizing...' screen until they are all ready.

When everyone has completed their training, you'll all see the starting cutscene and then awaken upon the Von Braun.

Play it ALONE for your first ever playthrough!
I've said it before and I'll say it again; If you're new to this game, make sure that your first ever time experiencing this game is alone.

Save Often!
This can not be stated enough. The game's multiplayer was made in 1999! It may crash, freeze and generally cause misery for people and yourself if you do not save often!

The best places to save your progress are before moving to other bulkheads and decks. You have been warned!

Mod Info
Cosmetic mods such as texture upgrades, weapon models, sound effects are fine to use BUT if you are going to use any modifications that change files such at the levels, SHOCK2.GAM or basically anything that ISN'T cosmetic, You will need to make sure that ALL people playing in your co-op session have the same files. If not, strange things may happen but the worst will be a game crash.

Share Stuff!
You may get your own money and Cybernetic Modules but don't go hogging all the goodies! Some players may be good at weapons you're not or someone might need that Psi-hypo you just picked up. Share to survive.

Don't Rush!
System Shock 2 is a game to be played slowly. Heavy exploration is required in order to find some well hidden items lying around the ship so take your time with it.

That is all. Enjoy one of the finest FPS-RPGs ever created with your friends.